Britain's Jenson Button wins world championship

REUTERS - Jenson Button and his Brawn GP team were crowned Formula One champions with a race to spare in an action-packed Brazilian Grand Prix won by Red Bull's Australian Mark Webber on Sunday.

Button finished fifth to become Britain's 10th world champion, with closest rival and team mate Rubens Barrichello suffering a late puncture and crossing the line eighth after starting his home race on pole position.

Button, who belted out an off-tune "We Are The Champions, My Friends" over the team radio on his slowing down lap, was ecstatic after a rain-hit qualifying session had left him starting 14th.

"Oh what a race. I am world champion, I am world champion. It's been such an interesting season," he said, embracing his mechanics before a congratulatory hug from Formula One supremo Bernie Ecclestone.

"It is really amazing. Today was such an awesome race and I am world champion. I never expected to be world champion in Formula One.

Webber celebrated the second won of his career.

"I think he (Button) can sleep better now because he's been absolutely bricking it after the last few races," Webber said with a smile. "He can enjoy (the last race in) Abu Dhabi."

Red Bull's Sebastian Vettel, the 22-year-old German who had needed to finish in the top two to have a chance of staying in contention for the title, took fourth place on a hot and humid afternoon at Interlagos.

Button, winner of six of the first seven races, now has 89 points to Vettel's 74 and Barrichello's 72.

Brawn, who had needed only a point to be sure of the constructors' championship, become the first team to take the crown in their first full season.

Third place

Poland's Robert Kubica was second for BMW-Sauber with McLaren's outgoing world champion Lewis Hamilton taking third place from 17th on the grid at the circuit where he clinched the title in a 2008 thriller.

The safety car was deployed for four laps after chaos on the opening lap when Force India's Adrian Sutil, Toyota's Jarno Trulli and Renault's Fernando Alonso crashed out.

Trulli and Sutil, who had been third on the grid, then had a heated argument on the run off with the Italian clearly feeling more aggrieved.

McLaren's Heikki Kovalainen finished the race with a stewards' investigation still pending after he left the pits with the fuel hose still attached, spraying fuel over Kimi Raikkonen's Ferrari.

The fuel then ignited, causing a flash fire near the pit lane wall.

Button, who had prayed for dry conditions after the deluge on Saturday, was by then on a charge and putting it all on the line, overtaking Renault's Romain Grosjean, Williams's Kazuki Nakajima and Toyota's Kamui Kobayashi.

Nakajima crashed spectacularly on lap 31 after touching Kobayashi's rear wheels.